bro,as few members said before, i dont know whether this topic have been discussed before but i wanna know what the best piping size for 4g91,4g92(non-mivec) and 4g93.
and also is it a good idea to plud and play mivec's OEM extractor to these 4g9series or go for 4-2-1 extractor that u can find in exhaust shops??
and also, whats the different between the standard pipe and stainless steel material?? looking into performance obviously..
and the centre bullet, i know its for reducing the noise, but what abt the performance site?? have it or lose it??
thanks allot for ur time...
Hey bro, my own opinion would be for:
4g91= 1.7"
4g92(non-mivec)= 1.7" or 1.85"
4g93 = 2" or 2.2"
*piping size may varies depending on the mods u done with the engine.
*piping size that i proposed is diameter of the piping
*if you want to have better torque or uphill power, don't get bigger size if u have option becoz bigger size piping only shifts the power band at higher range which means rpm drop faster after gear shifts due to least of backpressuring (condition for NA engine with low mods)
As for extractor, i would say it is good to change extractor. Nowadays, 4-2-1 has been a hybrid version which gives low end and high end benefits. But choosing the right one for your engine is kinda hard becoz piping bends and piping sizes differs in exhaust shops. Well, if the condition of the 4g9 series is good, why not use it? At least it comes stock with the engine.
Stainless steel and galvanized steel differs at the quality and also the thickness. Performance wise i would say same. It is just the matter of the shiny looking. Sometimes, it produces different exhaust note. (hard to say)
Always there is an argument on bullet and midbox. Well, i would say that bullet is much more likely for performance due to its straight flow shaping while midbox is a flatty type which gives restriction to the exhaust flow. Another thing is that the stock midbox always give some hollow noise due to non-fiber condition. It reduces noise by reflection while nowadays the midbox that u can buy is filled with fiber to absorb noises (not reflection). So, in conclusion, bullet is just better to have lesser restriction than a midbox and having no bullet/midbox in a system is NOT advisable due to a few factors.
Hope you understand my 'grandpa' stories. Should you need any help, call me anytime, if i'm free, i will pick up..else :)
CONTACT: Weng - 0125629713
hehehe, same question i ask in d last post.... thanks kweng
No problem bro. UGPM also!